Someone needs to sit the Labour party down and tell it a difficult truth. Nick Clegg isn't your secret friend. He hasn't spent five years in parliament being sneered at by Labour MPs and patronised by Gordon Brown in order to keep you in power just because the polls suggest you might come third. He thinks, as a party, you are dead – not just temporarily unpopular, or a bit tired, or caught between a dull gerontocracy and a subservient younger generation who don't dare remove the old – but ideologically empty and harming the people you say you help. A relic of Britain's industrialised, class-obsessed past.

Right now, it is easy for you to think of the Lib Dems as a sort of emergency fuel tank, a backup to boost your party above a sagging Tory vote. There are, after all, lots of things you both believe. One of them is that you would both like to replace Gordon Brown. So when Labour ministers see that Clegg describes the prime minister as "desperate" in today's Telegraph, many will privately agree. And when they heard Clegg tell the Commons, just before the election, "You've failed. It's over. It's time to go", they probably thought it was Brown he meant.

But it wasn't only Brown. It was Labour. He doesn't want to join the Labour party as a junior partner in some progressive alliance – he remembers what happened when Tony Blair offered Paddy Ashdown one of those. He is a liberal. Not a socialist or social democrat. He thinks the centralising, controlling, interfering, blundering state should be replaced by a liberal society, in all its forms. That's why, to pick an example, he is so keen on taking the poorly paid out of income tax, rather than taxing them and then deciding what to give back.

He wants the Lib Dems, over several elections, to replace Labour as Britain's liberal progressive force. Maybe that sounded absurd to you, until this week. It shouldn't anymore.